Vancomycin is a branched tricyclic glycosylated non ribosomal peptide antibiotic produced by the fermentation of the Actinobacteria species Amycolaopsis orientalis, and is believed to act by inhibiting proper cell wall synthesis in Gram-positive bacteria. Additionally, it is believed that vancomycin alters cell membrane permeability and RNA synthesis. Accordingly, vancomycin is generally used in the prophylaxis and treatment of infections caused by Gram-positive bacteria that are unresponsive to other types of antibiotics.
Vancomycin has been reported as a treatment of last resort for infections that are resistant to other first line antibiotics. This is because vancomycin is given intravenously for most indications. Additionally, vancomycin presents toxicity concerns, and semi-synthetic penicillins have been developed and used preferentially over vancomycin. Nevertheless, the use of vancomycin has increased particularly with the spread of multiple-resistant Staphylococcus aureus (MRSA).
Methods for treating pulmonary disorders using liposomal vancomycin formulations are described in U.S. Publication Nos. US 2009-0105126 and US 2009-0104257, and U.S. Provisional Application Nos. 61/103,725 and 60/981,990, all of which are hereby incorporated by reference in their entireties. There is a need in the art for cost-effective vancomycin formulations that degrade at a slower rate and therefore exhibit improved stability. The present invention addresses these and other needs.